org.apache.calcite.tools.Planner Maven / Gradle / Ivy
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/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to you under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.calcite.tools;
import org.apache.calcite.plan.RelTraitSet;
import org.apache.calcite.rel.RelNode;
import org.apache.calcite.rel.RelRoot;
import org.apache.calcite.rel.type.RelDataType;
import org.apache.calcite.rel.type.RelDataTypeFactory;
import org.apache.calcite.sql.SqlNode;
import org.apache.calcite.sql.parser.SqlParseException;
import org.apache.calcite.util.Pair;
/**
* A façade that covers Calcite's query planning process: parse SQL,
* validate the parse tree, convert the parse tree to a relational expression,
* and optimize the relational expression.
*
* Planner is NOT thread safe. However, it can be reused for
* different queries. The consumer of this interface is responsible for calling
* reset() after each use of Planner that corresponds to a different
* query.
*/
public interface Planner extends AutoCloseable {
/**
* Parses and validates a SQL statement.
*
* @param sql The SQL statement to parse.
* @return The root node of the SQL parse tree.
* @throws org.apache.calcite.sql.parser.SqlParseException on parse error
*/
SqlNode parse(String sql) throws SqlParseException;
/**
* Validates a SQL statement.
*
* @param sqlNode Root node of the SQL parse tree.
* @return Validated node
* @throws ValidationException if not valid
*/
SqlNode validate(SqlNode sqlNode) throws ValidationException;
/**
* Validates a SQL statement.
*
* @param sqlNode Root node of the SQL parse tree.
* @return Validated node and its validated type.
* @throws ValidationException if not valid
*/
Pair validateAndGetType(SqlNode sqlNode) throws ValidationException;
/**
* Converts a SQL parse tree into a tree of relational expressions.
*
* You must call {@link #validate(org.apache.calcite.sql.SqlNode)} first.
*
* @param sql The root node of the SQL parse tree.
* @return The root node of the newly generated RelNode tree.
* @throws org.apache.calcite.tools.RelConversionException if the node
* cannot be converted or has not been validated
*/
RelRoot rel(SqlNode sql) throws RelConversionException;
/** @deprecated Use {@link #rel}. */
@Deprecated // to removed before 2.0
RelNode convert(SqlNode sql) throws RelConversionException;
/** Returns the type factory. */
RelDataTypeFactory getTypeFactory();
/**
* Converts one relational expression tree into another relational expression
* based on a particular rule set and requires set of traits.
*
* @param ruleSetIndex The RuleSet to use for conversion purposes. Note that
* this is zero-indexed and is based on the list and order
* of RuleSets provided in the construction of this
* Planner.
* @param requiredOutputTraits The set of RelTraits required of the root node
* at the termination of the planning cycle.
* @param rel The root of the RelNode tree to convert.
* @return The root of the new RelNode tree.
* @throws org.apache.calcite.tools.RelConversionException on conversion
* error
*/
RelNode transform(int ruleSetIndex,
RelTraitSet requiredOutputTraits, RelNode rel)
throws RelConversionException;
/**
* Resets this {@code Planner} to be used with a new query. This
* should be called between each new query.
*/
void reset();
/**
* Releases all internal resources utilized while this {@code Planner}
* exists. Once called, this Planner object is no longer valid.
*/
void close();
RelTraitSet getEmptyTraitSet();
}
// End Planner.java